(REH-troh-PAYR-ih-toh-NEE-ul) 
Having to do with the area outside or behind the peritoneum (the tissue that lines the abdominal wall and covers most of the organs in the abdomen).
(REH-troh-PAYR-ih-toh-NEE-ul)
Having to do with the area outside or behind the peritoneum (the tissue that lines the abdominal wall and covers most of the organs in the abdomen).